Synthetic detergent milled flakes



Patented Nov. 25, 1 952 UNITED STATES PATENT OFFICE.

SYNTHETIC. DETERGENT MILLED FLAKES Robert Franklin Hald, Nutley, N; J.,.assignor'to" Colgate-PalmoliveePeet Company, Jersey City, N. .J acorporation of Delaware No Drawing, Application December 5-, 1949,Serial No. 131,249

81Claims.

1- This invention relates to novelcompositions and for-ms of syntheticdetergents and particularly to synthetic detergents which are in the areparticularly convenient for many uses sincethey present a large surfacearea and yet theydo not contain large amounts of dustand-do-not tend tocake within a pack-age'or form lumps when added to warm water. Soapchips: are generally about -to -thousandths of' an inch or more inthickness and therefore dissolve rather slowly whereas soap flakesprod'uced'by milling soap are usually from about 1 to- 5 thousandthsofan inch in thickness and-dissolve very quickly.

The soap compositions used in producing thin, milled soap flakesgenerally contain about 90% of organic material and only about 2 or3% ofinorganic salts, the remainder beingmoisture. Flakes produced from suchcompositionsare sufficiently plastic. and pliable to permit them to bereadily handled without crumbling or breaking and they do-not dry out orbecome dusty on long standing. On the other hand, if the inor-- ganicsalt content of the soap composition exceed's about 10% of' its weight,-the moist'urecontent of the soap must be increased inorder to permitmilling of the soap and even then the composition cannotbe reduced inthickness-much below 10 thousandths ofan inch. Moreover, the resultingvflakes are. brittle and tend to dry out or' crumble into a powder ordusty product on long: standing'or exposure to. the atmosphere.

Numerous synthetic detergents have been developed in recent years whichdifferfrom soaps in that they: are composed of'the salts of su'lfatedorsulfonated organiccompounds. In their most usual commercial form suchsynthetic detergents contain from about 50 to 75% of inorganic saltswhich are produced at least inpart by neutral izati'onaof the sulfationor sulfonation reaction mixture: in which there is an excess of thesulfatingor sulfonating agent. Only about or so of such products isusuallyactive ingredients, i. e.,v the neutralized sulfate or sulfon-ateof the organic material. For this reason synthetic detergents possessvery little inherent plasticity or strength and have not heretofore beencapable of. being. milled to produce a satisfactory thin 2 flakedproduct. When flakes formed; of? synthetic detergent. compositions havebeen: produced they have always crumbledv readily and broken downintosmall pieces or. particlesand dust, particularly when shaken about ortumbled during packaging and handling; When. filled intoa package theflakes soon'settle'in the package.- so-that the user on: openingthepackage'will find it only partially filled with a product ofunattractive appearancefrom-Which dust, may arise to irritate thenoseandimucousmembranes.

It has-now been discovered that, synthetic detergents can be'converted'into flakeswhichare only a few thousandthsrofaninch. in. thicknessandyet possess the desired flexibility or noncrumbling' characteristicsnecessary to. enable them to behandled, packaged: and shipped Withoutobjectionable crumbling. Furthermore; the composition can be milled andthe-flakes, produced have a glossy, brilliant and, transparentappearance; Compositions and products of this character are. produced byadding asuitable softening agent to the synthetic detergent composition.It has further been, discovered that the amount of the softening agentrequired is extremely limited and may be-no more than-a small fractionof the amountofinorganic saltsin the product.

One of the objects of the present invention is to produce syntheticdetergents in' the form of thin flakes which will not crumble readily.

Another object of the invention isto provide a synthetic detergentproduct having a novel composition, form and appearance.

These and. other objects and features of the present invention willappear from thefollowing description thereof, in which reference is madeto specific examples. of products and procedure embodying the. inventionfor the purpose-ofiii-- dicating. the nature ofthe invention but Withoutintending to limit the scopethereof.

This application is. a continuatiomirr-Dfiit. of application SerialNumber 563,457, filed November 14, 1944.

The synthetic, detergents. which may be'used in the present. inventionare, characterized by the presence in the molecule of an alkylradicalhaving from 8 to 22, preferably. 10 to 18, carbon atoms and asulfate or sulfonate group. They maybe described as salts of organicsulfuric acid reaction products such as are obtained by neutralizing thereaction mixtures of sulfuric acid (or other sulfonating agent) and anorganic compound having an alkyl chain of the stated length and a groupwhich is reactive with sulfuric acid. Such a group may be, for example,

an unsaturated linkage (C=C) preferably near a terminal carbon such asin higher olefines; a hydroxyl substituent (COH) such as in fattyalcohols, mono and diglycerides of fatty acids; an aromatic substituentsuch as a benzene rin which may itself be substituted as in phenols,toluene, xylene, etc.

A typical synthetic detergent from which compositions and productsembodying the present invention may be produced is that comprising fromabout 30 to 50% by weight of the sodium salt of coconut oilmonoglyceride monosulfate and from 50 to 70% of sodium sulfate. Similarproducts containing the ammonium salt of coconut oil monoglyceridemonosulfate also may be used and the invention is applicable to productsin which the synthetic detergent is an alkali metal (e. g., sodium orpotassium), alkaline earth metal (e. g., calcium or magnesium), ammoniumor other water-soluble salt of the sulfuric acid reaction product. Otherspecific examples of synthetic detergents contemplated by the presentinvention are sodium lauryl sulfate, the sodium salts of sulfated fattyalcohols produced from coconut oil, palm kernel oil, tallow, and otherrelated oils and fats, sodium monolaurin monosulfate, ammonium dilaurinmonosulfate, sodium salts of esters of 1,2 dihydroxy propane-3 sulfonicacid with higher fatty acids derived from fats and oils of the statedtypes, water soluble salts of alcylated aromatic sulfonic acids such assodium dodecyl benzene sulfonate, the sodium salts of the sulfonatedalkane produced by condensing a paraffin fraction of predominately 12carbon atom chain length with benzene, alkyl sulfoacetates such assodium lauryl sulfoacetate, fatty acid esters of taurine such as theammonium salt of oleic acid amide of N-methyl taurine, fatty acid estersof hydroxy alkyl sulfonic acids such as the sodium salt of oleic acidester of isethionic acid, the magnesium salt of the mixed sulfates ofmonoglycerides of coconut oil and tallow, etc. It is to be understoodthat these specific examples are given by way of illustration and notlimitation and that any normally solid water-soluble salt of a sulfatedor sulfonated organic compound having pronounced detersive propertiesmay be used in the present invention.

Each of the foregoing synthetic detergents may be used in combinationwith from 30 to 70% or more of inorganic salts produced as an incidentto the manufacture of the detergent or added thereto as a builder, orfor other purposes. Compositions of this character are in no casecapable of use by themselves to produce a thin, bright, non-crumblingsynthetic detergent flake. They are difilcult to mill and when attemptsare made to reduce the composition to the form of thin flakes theproduct invariably is brittle or crumbles readily and tends to breakdown into dust or small particles.

In accordance with the present invention small amounts of suitablesoftening agents are added to these compositions and as a result a newtype of composition is produced which differs markedly from thecomposition treated and may be milled readily and formed into flakeswhich are from .001 to .005 inch in thickness. Furthermore, the flakesproduced possess sufficient strength or cohesion to withstandconsiderable jarring, vibration and agitation such as that incident topackaging and shipping of th product. The flakes do not crumble readilyor break down into dust to an objectionable extent, and

'4 they have a brilliant, glossy and in some cases even transparentappearance that renders the product most attractive.

The amount and character of the softening agent used may be variedconsiderably but the quantity required to produce a satisfactory flakedsynthetic detergent is very small and generally is no more than about 5%of the total weight of the finished composition and less than 15% of theweight of the inorganic salts in the composition. In the preferred formof the composition only about 1% by weight of the softening agent isused.

Typical softening agents employed in the milled flakes of the inventionare polyhydric alcohols such as glycerine, sorbitol, and ethyleneglycol; fatty acids having at least 6 carbon atoms and up to 22' carbonatoms per molecule, preferably the higher saturated acids such asmyristic, palmitic and stearic acids, either alone or admixed with otherfatty acids, e. g., as in hydrolyzed natural oils and fats, or insynthetic mixtures of such fatty acids; and monoesters of polyhydricalcohols with such fatty acids, e. g., monoglyceryl stearate, monoglycolpalmitate, monoglyceryl laurate, monoglycerides of coconut oil, palm oiland olive oil fatty acids, etc.

These agents may be added to the synthetic detergent compositions in anysuitable way and blended therewith by mixing, kneading or similaroperations and by means of any preferred type of equipment.

In order to illustrate typical practice in accordance with the presentinvention the following example is cited:

parts of a synthetic detergent containing 35 parts of the sodium salt ofcoconut oil monoglyceride monosulfate and 65 parts of sodium sulfate,are mixed with 1 part of coconut oil monoglyceride in apparatus such asa conventional soap amalgamator or dry powder mixer. If desired aperfume may be added to the mixture during this operation. The productis then milled on a conventional 5-roll mill at a temperature of fromabout to F. until a sheet of the desired thickness, say 1 to 5thousandth of an inch in thickness is produced. The flakes produced fromthis sheet are bright, glossy and semi-transparent and do not crumble orbreak down into dust or small particles even when vigorously shaken. Theproduct does not cake on standing and dissolves quickly in warm waterwithout lumping, producing a thick foam even in hard or salt water.

Another composition which is typical of the present invention may beproduced by blending 1 part by weight of glycerine with 100 parts byweight of a synthetic detergent containing 32 parts by weight ofpotassium salt of coconut oil monoglyceride monosulfate and 68 parts byweight of potassium sulfate.

In producing a further composition 5 parts by weight of stearic acid areblended with 100 parts by weight of a synthetic detergent containing 40parts of the sodium salt of lauryl sulfate and 60 parts of sodiumsulfate.

Similarly, other synthetic detergents and other softening agents whichare water dispersible, non-volatile and capable of blending with ordissolving in the synthetic detergent may be employed. The amount of thesoftening agent used should not be sufficient to render the productsticky or to impair the detergent properties of the product butpreferably is sufficient to permit the composition to be milled toproduce flakes which are no more than about 1 to 5 thousandths of aninch in thickness. In most cases an amount of softening agent notexceeding about 5% of the total Weight of the synthetic detergentcomposition is preferred.

If desired the softened synthetic detergent composition may be convertedinto forms other than flakes and it may be mixed or blended with othercompositions, builders, fillers, detergents, or the like to producenovel products. In view thereof it should be understood that theparticular and preferred forms, compositions and procedures describedabove are intended to be illustrative of the present invention and arenot intended to limit the scope thereof as defined in the followingclaims:

What is claimed is:

1. Milled synthetic detergent flakes consisting by weight essentially ofabout 30% to 50% watersoluble salt of an organic sulfuric acid reactionproduct having in its molecular structure an alkyl radical of 8 to 22carbon atoms, about 50% to 70% of inorganic sulfate salt having the samecation as said organic salt, and about 1% to 5% of a softening agentfrom the group consisting of polyhydric alcohols, fatty acids having 6to 22 carbon atoms and monoesters of polyhydric alcohols with fattyacids having 6 to 22 carbon atoms.

2. Milled synthetic detergent flakes as set forth in claim 1 in whichthe water-soluble salt is sodium alkyl sulfate.

3. Milled synthetic detergent flakes as set forth in claim 1 in whichthe water-soluble salt is sodium monoglyceride monosulfate.

4. Milled synthetic detergent flakes as set forth in claim 1 in whichthe water-soluble salt is sodium benzene sulfonate.

5. Milled synthetic detergent flakes as set forth in claim 1 in whichthe water-soluble salt is sodium alkyl sulfonate.

6. Milled synthetic detergent flakes as set forth in claim 1 in whichthe softening agent is a monoglyceride.

7. Milled synthetic detergent flakes as set forth in claim 1 in whichthe softening agent is a higher saturated fatty acid.

8. Milled synthetic detergent flakes as set forth in claim 1 in whichthe softening agent is glycerine.

ROBERT FRANKLIN HEALD.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,166,315 Martin July 18, 19392,236,628 Muncie Apr. 1, 1941 2,298,650 Samaras et al Oct. 13, 19422,364,767 Zizinia Dec. 17, 1944 2,391,087 Donlan Dec. 18, 1945

1. MILLED SYNTHETIC DETERGENT FLAKES CONSISTING BY WEIGHT ESSENTIALLY OFABOUT 30% TO 50% WATERSOLUBLE SALT OF AN ORGANIC SULFURIC ACID REACTIONPRODUCT HAVING IN ITS MOLECULAR STRUCTURE AN ALKYL RADICAL OF 8 TO 22CARBON ATOMS, ABOUT 50% TO 70% OF INORGANIC SULFATE SALT HAVING THE SAMECATION AS SAID ORGANIC SALT, AND ABOUT 1% TO 5% OF A SOFTENING AGENTFROM THE GROUP CONSISTING OF POLYHYDRIC ALCOHOLS, FATTY ACIDS HAVING 6TO 22 CARBON ATOMS AND MONOESTERS OF POLYHYDRIC ALCOHOLS WITH FATTYACIDS HAVING 6 TO 22 CARBON ATOMS.